States with the most super-rich residents

In the increasingly top-heavy world of wealth, $30 million is the new $1 million. And the number of people with a net worth of $30 million or higher is growing rapidly in the U.S., especially in California and New York.

According to a new report by Wealth-X and UBS, there are now 69,560 Americans worth $30 million or more, which Wealth-X refers to as "ultra-high net worth individuals." These super rich are highly concentrated on the coasts in New York and California, with the two states adding the largest number of super-rich residents over the past year.

California's population of ultra-high net worth residents grew 7 percent, to a total of 13,445. That's higher than the total for the entire United Kingdom, which has 11,510 ultra-high net worth residents. Almost all of California's super rich were located in San Francisco (5,460) and Los Angeles (5,135).

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California added 865 new super-rich residents and New York added 585, with 91 percent of those New Yorkers living in New York City. In fact, California and New York combined added more new super-rich residents in just one year than the entire ultrawealthy populations of all but a handful of states.

The state with the fastest percentage growth in $30 million-plus residents was North Dakota with 14.3 percent growth, followed by South Dakota with 13.3 percent.